• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.160-168
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• 1995

Desmutagenicities against 2-amino-1-methyl-6-phenylimidazo[4, 5-b] pyridine(PhIP) and 2-amino-3, 8-dimethylimidazo[4, 5-f]quinoxaline(MelQx) of tea extracts (steamed green tea, roasted green tea, oolong tea and black tea) were investigated. All the fractions obtained from tea extracts showed strong desmutagenic activity against PhIP and MeIQx toward S. typhimurium TA 98 in the presence of the S-9 mix. The crude catechin fraction exhibited the strongest desmutagenic activity. Among these tea extracts, black tea especially exhibited the strongest desmutagenic activity and the activity was 70.9~91.0% against PhIP and 92.2~98.8% against MelQx at a concentration(0.5~1.0mg/plate) for drinking. The activity of authentic catechins of (-)-EGC, (-)-EGCg, (-)-ECg and (-)-EC were 79.5%, 60.2%, 46.1% and 43.5% against PhIP, and were 52.3%, 11.6%, 8.2% and 22.1% against MelQx by addition of 1.0mg/plate, respectively. The desmutagenic activity was supposedly due to the (-)-EGCg, (-)-EGC and (-)-EC in tea polyphenols, and the browning materials. The desmutagenicity was stronger when mutagens were preincubated with S-9 mix after reaciton with black tea extracts than when preincubated with them after reaction with S-9 mix. The desmutagenicity of tea extracts was rather expressed by reacting directly with mutagens than by deactivating the activated forms of mutagens.

• Korean Journal of Microbiology
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• v.36 no.1
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• pp.64-68
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• 2000

The immunopotentiating effects of the polysaccharides, both intracellular and extracellular, was examined by an animal feeding test. The results are summarized as follows. The oral administration of intracellular and extracellular polysaccharides of Agrocybe cylindracea for 10 days resulted in the enhanced phagocytic activity of peritoneal exudate cells(PEC), spleen cells(SC), and monolymphocytes(ML). In the experiment of PFC(plaque forming cell) and RFC(rosette forming cell), the results showed that all the polysaccharide fractions enhanced the immune related cells. The EAC II group(the extracellular polysaccharide of Agrocybe cylindracea 10 mg/0.2 ml distilled water/day/ mouse) increased the PFC and RFC by 46~50% and 43%, respectively, compared to the control group. On the other hand, the IAC I group(the intracellular polysaccharide of Agrocybe cylindracea 1 mg/0.2 ml distilled water/day/mouse) increased the PFC and RFC by 49~70% and 91%, respectively. In terms of the mitogenic activity, the extracellular polysaccharides of A. cylindracea showed a higher activity than the intracellular polysaccharides.

• Journal of KIISE:Information Networking
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• v.29 no.2
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• pp.197-203
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• 2002

This paper proposes a new agent based mechanism called a Multicast Handoff Agent (MHA) to reduce handoff latency for IP multicast. The MHA acts as a proxy for an Internet Group Management Protocol (IGMP) of Mobile Nodes (MNs) at each Base Station (BS) and keeps information for members of multicast groups in a cell. When an MN moves to a next cell, the MHA immediately sends unsolicited reports without waiting for the IGMP query. The mechanism was evaluated through simulation and analysis and compared with the IGMPv2 for micro-mobility and the IGMP traffic. Simulation results show that handoff latency for micro-mobility can be largely reduced and the IGMP control traffic on the wireless links during the duration of membership can be eliminated. Thus, this mechanism is superior to the existing mechanism in both micro-mobility and battery duration, as the need not to reply to a query conserves battery power.

• Polymer(Korea)
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• v.27 no.1
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• pp.9-16
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• 2003

Ipriflavone (IP) stimulates proliferation and differentiation of osteoblast and also enhances calcitonin secretion in the presence of estrogen. Poly(lactide-co-glycolide) (PLCA) due to its controllable biodegradability and relatively good biocompatibility is one of the most significant candidates for the study of drug controlled release system. In this study, IP-loaded PLGA microspheres (MSs) was prepared by using conventional O/W solvent evaporation method. The size of MSs was in the range of 5~200 $mu extrm{m}$. The morphology of MSs was characterized by SEM. And, in vitro release amounts of IP were analyzed by HPLC. The highest encapsulation efficiency were obtained by using gelatin and polyvinyl alcohol (PVA) as emulsifiers. The morphology, size distribution, and in vitro release pattern of MSs were changed by several preparation parameters such as molecular weights (8, 20, 33 and 90 kg/mol), polymer concentrations (2.5, 5, 10 and 20%), emulsifier types (PVA, gelatin and Tween 80), initial drug loading amount (5, 10, 20 and 30%) and stirring speed (250, 500 and 1000 rpm). The release of IP in vitro was more prolonged over 30 days, with close to zero-order pattern by controlling the preparation parameters. The physicochemical properties of IP-loaded PLGA MSs were investigated by XRD and DSC.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.231-236
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• 2004

An imaging plate(IP) detector, a two-dimensional digital radiation detector that can acquire image of radioactivity distribution in a sample, has been applied in many fields; for industrial radiography, medical diagnosis, X-ray diffraction test, etc. In this study, the possibility of IP detector to be used lot measuring radioactivity of sample is explored using its high sensitivity, higher spatial resolution, wider dynamic range and screen uniformity for several kinds radiations. First, the IP detector is applied to measure the surface uniformity for area source. Surface uniformity is measured rapidly and nondestructively by measuring the radioactivity distribution of common standard area source$(^{241}Am)$. Next, the IP is employed to study the possibility of measuring an extremely low-level activity of environmental sample. For this study the screen uniformity, shield effect of background radiation, linear dynamic range and fading effect of the IP detector is investigated. The potato, banana, radish and carrot samples are chosen to measure ultra low-level activity of $^{40}K$ isotope. The efficiency calibration of IP detector is carried out using the standard source.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.20-29
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• 2014

Recently, LTE is preparing to make a new leap forward LTE-A all over the world. As LTE privides high speed service, the role of mobile phones seems to change from voice to data service. According to Cisco, global mobile data traffic will increase nearly 11-fold between 2013 and 2018. Mobile video traffic will reach 75% by 2018 from 66% in 2013 in Korea. However, voice service is still the most important role of mobile phones. Thus, controllability of throughput and low BLER is indispensable for high-quality VoIP service among various type of traffic. Although the maximum AMR-WB, 23.85 Kbps is sufficient to a VoIP call, it is difficult for the LTE which can provide tens to hundreds of MB/s may not keep the certain level VoIP QoS especially in the cell-edge area. This paper proposes a new scheduling algorithm in order to improve VoIP performance after analyzing various scheduling algorithms. The proposal is the technology which applies more priority processing for VoIP than other applications in cell-edge area based on two-tier scheduling algorithm. The simulation result shows the improvement of VoIP performance in the view point of throughput and BLER.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.2 s.344
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• pp.66-75
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• 2006

This paper addresses the implementation of FTTH system based on Ethernet PON technololy. This system consists of OLT and ONT. OLT supports the maximum 24 Gigabit Ethernet interfaces, and then has the flexibility and the scalability for supplying digital communication and broadcasting convergence service in the near future. OLT system consists of switch module, subscriber module, processor module, and E-PON link module, and has the operating system based on Linux. ONT is installed in customer premise to supply both IP-TV and Internet service. Also ONT has the dedicated interface for IP-TV to improve the transmission characteristics of IP-TV signal. We measure the performance of E-PON MAC through this system and then QoS control characteristics per franc in ONT by separating the virtual link for IP-TV from that for data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6A
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• pp.445-454
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• 2005

To measure the performance of call quality, we have built the experiment environment and observed that the delay caused by encapsulation between internet and VoIP telephones is under 5ms at most. The major delay is assumed to be the time required to capsulate the packet for tunnelling of VPN. Because the difference of average delay time is under $4ms{\sim}5ms$, the difference of call quality between VoIP and VoIP telephone adopting VPN is negligible. We have concluded that the capsulation process between PAC and PNS is the major factor influencing the network load by changing the number of fames in a packet during communication Also, we have concluded that the most suitable frame numbers is tow or three by adding the frame numbers in a packet to obtain the suitable frames in a packet and setting up end-to-end delay under 150ms.

• Journal of Arbitration Studies
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• v.17 no.2
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• pp.71-100
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• 2007

To promote the way of resolving the increasing disputes regarding international intellectual property by arbitration, we should overcome uncertainty thwarting the dispute resolution; i.e., whether a dispute regarding intellectual property would be an arbitrable subject, whether the arbitration agreement would be valid and enforceable, and whether the arbitral award could be recognized and enforced in a foreign country. This article is intended to seek how to promote and facilitate the resolution of international disputes regarding intellectual property by arbitration. This article in Chapter II will examine the characteristics of the IP disputes first. Chapter III of this article will study arbitrability of IP disputes. Then, Chapter IV will discuss the requirements, validity, and effectiveness of arbitration agreement of international IP disputes. The author will discuss the procedure of arbitration of the international IP disputes in Chapter V, and finally the recognition and enforcement of foreign arbitral awards thereon in Chapter VI. Due to the so called 'territoriality principle' in intellectual property, the international disputes thereof confront numerous procedural setback, e.g., jurisdiction, conflict of laws, the recognition and enforcement of foreign judgments or awards. To overcome such setbacks, I propose resolution of international IP disputes by one-step arbitration procedure through widely recognizing the arbitrability of IP disputes, and utilizing unnational nature of arbitration. In addition, I propose to set up the principles as to arbitration of the international IP disputes as the American Law Institute has formulated the principles for International Intellectual Property Litigations. By setting up these principles, I am certain it will be helpful to just and prompt resolution of international IP disputes which occur more frequently these days.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.60-67
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• 2013

Test cost reduction is necessary to test a complex System-on-a-Chip(SoC) which adopts various Intellectual Properties (IP). In this paper, test architecture with low pin count which is able to IP-based SoC test, using IEEE Std. 1149.7 and IEEE Std. 1500, is proposed. IEEE Std. 1500 provides independent access mechanism for each IP in IP-based SoC test. In this paper, just two test pins are required by composing that these independent access mechanism can be controlled by IEEE Std. 1149.7. The number of Chips which are tested at the same time is increased by reducing required test pin count at wafer and package level test, and consequently the overall manufacturing test cost will be reduced significantly.